Water quality management

As the nation's oldest multipurpose water reclamation project, SRP operates and maintains an irrigation system that typically delivers more than 325 billion gallons of water to municipal, industrial, agricultural and urban irrigation systems each year.

Water in the 131-mile-long canal system is a mix from the Salt and Verde rivers, the Central Arizona Project canal, groundwater pumped from wells, and storm water and agricultural return flows. SRP takes a variety steps to protect and monitor these water resources.

SRP works with the Arizona Department of Environmental Quality to address known pollution problems through special projects. SRP also collaborates with the City of Phoenix and other communities in the Phoenix metropolitan area to implement water conservation measures and programs to monitor and protect water quality. In addition, SRP routinely reviews the proposed waste-water discharge permits of non-SRP facilities to ensure that the water resources we manage are protected.

SRP monitors the water quality of both surface and groundwater supplies, and has undertaken efforts to enhance the program. For example, nitrate probes have been installed along several SRP canals. Nitrate readings are transmitted back to a control center and adjustments are made to water operations to manage nitrates levels in the canals.

SRP also uses computer models to predict water quality conditions in the canal under varying operating parameters.

Water quality monitoring

One of SRP's most important water management programs is water quality monitoring. It provides information about patterns and trends in SRP surface and groundwater quality and also about potential pollution sources. SRP monitors the rivers within the watershed, as well as the canals and groundwater wells within its water service area.

In response to a rapidly urbanizing community and heightened awareness of public health issues related to drinking water, SRP has expanded its monitoring program to include testing of a greater number of potential pollutants in SRP canals and wells. SRP collects samples from various sites on the canals monthly. Wells are sampled once per year, usually during the summer in conjunction with pump testing activities. SRP has its own analytical laboratory, which is certified by the state of Arizona.

SRP also uses computer modeling to track flow conditions in the canals to help control nitrate levels in canal water upstream of water treatment plants. Although nitrate concentrations in surface water are relatively low, some groundwater wells contain relatively high concentrations and must therefore be mixed with surface water to reduce levels in the canals.

Managing our facilities

SRP manages its power plants and other facilities to protect surface and groundwater resources. All appropriate approvals and permits have been obtained for our facilities, such as those required under the federal Clean Water Act and the Arizonaâ€™s Aquifer Protection Program.

SRP performs all monitoring and reporting required by various water quality protection laws, regulations and permits. Permits or approvals are required for waste water discharges to surface waters and municipal sewer systems, storm water discharges from construction sites and other discharges that have the potential to reach groundwater.

SRP regularly audits its facilities and operations. When necessary, corrective actions are promptly taken to ensure compliance with applicable requirements. SRP is always working to reduce the volume of chemicals stored, used and discharged at its facilities. For example, one of SRP's power plants greatly reduced on-site storage of water treatment chemicals: the facility eliminated storage of 22,000 gallons of sodium hydroxide and reduced sulfuric acid storage from 20,000 to 1,000 gallons.

Another power plant reduced the on-site storage of sulfuric acid from 10,000 to less than 1,000 gallons and totally eliminated the on-site storage of 5,000 gallons of sodium hydroxide. These reductions were achieved by changing components of the water treatment system to minimize chemical usage at the facilities.

What you can do

Individuals can make a difference when it comes to preserving water quality. Among the steps you can take are:

Apply pesticides and fertilizers according to label directions. Do not over-apply. The excess can run off in storm water and contaminate surface waters or migrate to groundwater.

Do not pour hazardous chemicals, such as antifreeze, oil, paints, stains, polishes or solvents down a household drain, storm sewer, ditch or on the ground. Such actions can contaminate surface waters or groundwater.